This is how big cats were named.
"I HATE BIG CATS. THAT ONE IS A LIAR, THAT ONE IS A CHEATER. THE ONE IS A POO-MA."
"Lion. Cheetah. Puma. You're getting a promotion."
Listen up, buttercup. So, this joke is about how some big cats got their names. This dude is hating on cats, right? Calls one a liar, another a cheater, and then messes up "puma," calling it a "poo-ma." Then his boss is like, "Aha! I'll name them those things!" Get it? I bet you didn't. It's okay, happens all the time because you are not smart.